Using Quaternion for Lagrangians in EM and GEM, Cartesian

4,757 views · Published 30 March 2008 · 14:54 · Indexed 18 October 2026

Channel: Doug Sweetser · 2008 · Science & Technology

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Please see the "GEM Blog: GEM Unification Rescinded, Officially" video.

This talk shows how to derive the Maxwell equations starting from quaternions, a type of 4D number. A variation of the EM Lagrangian leads to the GEM field equations. A time dependent form of Newton's field equations can be seen in the GEM field equations, a good thing.

The equations are written in Cartesian coordinates, the ones which I am most comfortable.  Due to a question I was asked, I redid the derivation using manifestly covariant symbols.

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